P23FB code meaning
Cylinder 10 Injector B Air-Fuel Ratio Imbalance
Powertrain system Generic code P23xx codes Check engine light
What P23FB means
P23FB marks cylinder 10, the highest cylinder number of a V10. Among dual-injection engines, the Huracán's 5.2 litre unit is the documented case; it adds multi-point injection to direct injection. In its firing order cylinder 10 follows directly after cylinder 5. On a ten-cylinder engine an injector B deviation in cylinder 10 shows up mainly in the bank that includes cylinders 6 to 10, which is why a bank code (P219B) or a misfire code (P0310) may be the only entry. CARB requires imbalance detection for such cars too, and since 2019 to 2021 also tracking of how frequently the check runs to completion in everyday use. No manufacturer documents P23FB publicly. P21A5 and the circuit code P21D8 are the companion codes.
P23FB at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor2 to 8 hours
- Clears after repairAfter a drive cycle
Symptoms of P23FB
- Check engine light on
- Bank 2 or misfire code stored alongside
- Mostly no noticeable change
Common causes of P23FB
- Most likelyPort injector of cylinder 10 dirty or worn
- PossibleInjector seal leaking air at cylinder 10
- Less likelyHeat-damaged wiring to injector B of cylinder 10 (check P21D8)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Fuel injector b cyl 10
What each part of P23FB means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 3 | Area: ignition system or misfire. |
| FB | The exact fault in that area. |
What to do next
- Note P23FB and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P23FB
What does P23FB mean?
P23FB means "Cylinder 10 Injector B Air-Fuel Ratio Imbalance". P23FB marks cylinder 10, the highest cylinder number of a V10. It is a generic code, so it means the same on every make.
Is it safe to drive with P23FB?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P23FB fail an emissions test?
Yes, it can. P23FB is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P23FB to fix?
Difficulty: workshop only. A typical repair takes 2 to 8 hours of work. This is a job for a workshop.
Will P23FB clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.